Mark Stewart was born in New York City and grew up in a publishing family. His mother, Helen Markel, was a freelance journalist who later served as articles editor for Ladies Home Journal and McCall’s. His father, John G. Stewart, was an editor at The New York Times. His grandfather, Lester Markel, who established the International Press Institute in 1951 and was awarded a Pulitzer Prize in 1953, was Sunday Editor of The New York Times from 1923 to 1964.

Mark has been building lean-and-mean freelance project teams since 1990. Since then he has worked with nearly 100 creative professionals, including writers, researchers, editors, proofreaders, designers, photographers, film makers, visual artists and social media experts.

Mark attended the Ethical Culture Fieldston School in New York and graduated with a degree in history from Duke University in 1984.

In 2021, Mark and his wife purchased the historic William Wright Mansion in Columbia, Pennsylvania. Built by a wealthy Quaker family on the banks of the Susquehanna River, the structure served as the initial stop on the Underground Railroad in central Pennsylvania for many years. According to William Wright’s contemporary, abolitionist William Still, more than 1,000 freedom seekers began their journey to safety through the Wright house. The Stewarts are just the sixth family to own the home since its construction in 1795.

In 2022, Mark joined the effort to create The Underground Railroad Museum of Pennsylvania in Columbia.